It has been proposed that nitrilotriacetic acid be substituted for trisodium polyphosphates in detergents as a way to reduce the rate of eutrophication in the Great Lake Basin. The reaction of nitrilotriacetic acid with chlorine-containing solutions produces a hitherto unknown degradation production, N-formyliminodiacetic acid, in high yield. The toxicological and environmental implications of this reaction are unclear.